Jawabanmu

2014-03-19T08:12:53+07:00
2p= 5/9.81=45
p=45/2=22,5

2l=4/9.81=36
l=18

L= p.l
=22,5.18
=180m2
2014-03-19T10:07:08+07:00
5+4=9
81/18=4.5
Lebar=5*4.5=22.5
Panjang=4*4.5=18
Luas=22.5*18= 405m^{2}